It is conventional in the art of displacement measurement to employ a probe which provides an output that varies as a function of distance or displacement between the probe measurement tip and a target object. One type of displacement probe which has enjoyed substantial acceptance in the art employs a permanent magnet and a so-called Hall effect device for measuring distance to the target object as a function of variations in the magnetic field through the Hall device. Where such probes are employed in high speed applications, it is conventional practice to provide a lookup table which relates probe output to probe/target displacement and thus provides rapid measurement without requiring complex mathematical calculations. Such tables are typically generated to reflect average characteristics of the type or model of probe in question, and thus does not accurately reflect individual measurement characteristics of each probe. Consequently, accuracy of measurement is compromised.
A general object of the present invention is to provide a method of calibrating a displacement probe, such as a Hall effect displacement probe, which generates a look-up table unique to each probe and which thus enables more accurate displacement measurements during probe operation.
Another object of the invention is to provide a method of the described character which is economical to implement and which may be performed by relatively unskilled personnel.
A further object of the invention is to provide apparatus for calibrating displacement probes in accordance with the method of the invention.